1. Field of the Invention
The present invention relates to a processing method of quick response code (QR code) and a related apparatus, and more particularly, to a processing method of detecting and adjusting a QR code within an input image, and a related apparatus.
2. Description of the Prior Art
For business activities such as trading goods and inventory management, a one-dimension bar code provides a fast and convenient identification method. However, in our rapidly modernizing society, the information volume provided by the one-dimension bar code gradually becomes inefficient. Quick response code (QR code) is a two-dimension code developed by the Japanese corporation Denso Wave. Its original purpose was for vehicle part management. Compared with the conventional one-dimension barcode, QR code is capable of providing more information capacity since the content is stored in a two-dimension surface. Furthermore, when combined with modern technologies such as digital cameras and wireless network, QR code can provide an abundant variety of consumer related usages.
Please refer to FIG. 1, which is a diagram of a conventional QR code. A normal QR code includes a finder pattern, an alignment pattern, a timing pattern, a quiet zone, a format area and a data area, wherein the finder pattern and the timing pattern are tools for positioning a QR code and determining its size, and the alignment pattern is for correcting errors resulting from identification.
A surface where the QR code is located is very susceptible to projection distortion and unevenly distributed luminance such that following decoding processes may be unable to proceed and thereby a proper result cannot be derived. Please refer to FIG. 2 and FIG. 3. FIG. 2 is a diagram of a projection distortion of a QR code due to uneven distances between both sides of the QR code and an image capture apparatus (e.g., a digital camera). FIG. 3 is a diagram of a QR code partially covered by shadow (a slashed part on the upper right corner in FIG. 3). Both the cases described above tend to lead to failure of a QR decoder to correctly decode the content within the QR code. Therefore, how to derive a QR code properly in a given image is still a major issue in this field.